The standard answer is to engage an attorney to do a freedom to operate search and give you a written opinion. This presupposes that you know what you are building and how it works in some detail. The search would look for patents that are in force that have claims that look like they might cover what you are building.
Since you are in the early stages of development you might consider a "design-around" exercise. That involves identifying problematic patents, studying their claims (with professional help) and figuring out a way to accomplish the end you want without using the specific means to that end covered by the claims. One angle you might take is to look for things that came before - for example - the last google patent mentioned. Something listed in the google patent that came before the google patent is --
US5832502A 1996-07-02 1998-11-03
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Anything filed in 1996 will be long expired. Can you do what Microsoft did and not do what google has claimed? Of course this is just one of the several patents you located.
You might do the same for other references listed on each of the google patents. It is a lot of work. One way to narrow it might be to decide that your biggest worry are patents on something core to your value added that are owned by your biggest competitors.